No outcome difference between two treatments for wheezing preschoolers

Giving daily low doses of an inhaled corticosteroid to preschool-age children who have recurrent wheezing and are at risk for developing asthma does no better than intermittent high doses to control the condition, according to a study funded by the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health.

Current clinical guidelines recommend daily low-dose treatment for high-risk preschoolers who have recurrent respiratory illnesses that lead to wheezing.But adherence to daily treatment is less dependable. This study found that giving four times the daily low dose only when the children had specific respiratory illness symptoms had comparable effects while requiring one-third the total amount of medication per year.

The results appear online in The New England Journal of Medicine on Nov. 23, 2011.

"Recurrent wheezing in these very young children is a big problem. Parents and caregivers are reluctant to give them medicine every day when the wheezing episodes occur only a few times a year," said Susan B. Shurin, M.D., a pediatrician who is acting director of the NHLBI. "Studies such as this build evidence necessary for physicians and parents to make informed choices about treatment options."

The one-year study followed 278 preschool-age children between the ages of 1 and 4.5 years who were considered at high risk of developing asthma and had wheezing episodes during respiratory illnesses but who had very few or no symptoms between episodes.The children were randomly assigned to one of two groups. One group was treated daily with low doses of the inhaled corticosteroid budesonide (Pulmicort Respules 0.5 milligrams, or mg, per day). The second group was treated with a high dose of budesonide (2 mg per day) for seven days only when the child had respiratory illness symptoms like those that had previously led to a severe wheezing episode.

The study found no difference between the two treatment groups in the number of exacerbations (episodes requiring oral corticosteroids, which have more side effects than inhaled steroids); severity of respiratory symptoms; number of symptom-free days; number of doctor visits due to symptoms; absences from school, day care, or parental work; or quality of life.On average, the intermittent treatment was given every 3.5 months, exposing the group to a total dose that was one third that received by children in the daily treatment group.

"In medicine, our goal is always to treat children with the smallest amount of a drug that is still effective," said the study's principal investigator, Robert Zeiger, M.D., Ph.D., of the University of California, San Diego and Kaiser Permanente Southern California in San Diego. "Our study offers a treatment option for wheezing preschoolers. A critical element of the intermittent approach is that parents were taught to start the intermittent regimen so it was not used for every respiratory illness or symptom."

Zeiger added that while the study may benefit many preschoolers who wheeze during respiratory illnesses, it did not evaluate children who have more severe disease or persistent symptoms.

The study, called the Maintenance and Intermittent Inhaled Corticosteroids in Wheezing Toddlers, or MIST, trial, was conducted at seven sites as part of the NHLBI's Childhood Asthma Research and Education Network.

"This question represented a real gap in our evidence base in the asthma treatment guidelines," said James Kiley, Ph.D., director of the NHLBI Division of Lung Diseases."Filling these gaps is exactly what our clinical research programs are intended to do."

Part of the National Institutes of Health, the National Heart, Lung, and Blood Institute (NHLBI) plans, conducts, and supports research related to the causes, prevention, diagnosis, and treatment of heart, blood vessel, lung, and blood diseases; and sleep disorders. The Institute also administers national health education campaigns on women and heart disease, healthy weight for children, and other topics. NHLBI press releases and other materials are available online at www.nhlbi.nih.gov.

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